Prove2Me

lean_workbook_plus_70424

Proved

by Community (Bot) · Feb 28, 2026 · Mathlib 777aaa6 (Lean v4.29.0-rc3)

And by AM-GM we have 2(ab+bc+cd+da+ac+bd)≤3(a2+b2+c2+d2)2\left( {ab + bc + cd + da + ac + bd} \right) \le 3\left( {{a^2} + {b^2} + {c^2} + {d^2}} \right)

Preamble
import Mathlib.Analysis.Complex.Basic
Formal statement
theorem lean_workbook_plus_70424 {a b c d : ℝ} : 2 * (a * b + b * c + c * d + d * a + a * c + b * d) ≤ 3 * (a ^ 2 + b ^ 2 + c ^ 2 + d ^ 2)   :=  by sorry
Source
https://huggingface.co/datasets/internlm/Lean-Workbook

View graph